The design of IOT low-power equipment is roughly divided into three aspects: Device Selection, Circuit D
esign, Software Design and Endurance life estimation——
Circuit Design
For devices with large power consumption, use independent IC for power supply, and try to turn off the power supply circuit independently, and cut off the power supply circuit under the condition of abnormal power supply;
For the pull-down resistance, on the premise of ensuring good signal immunity, use high resistance value as far as possible; For example, for 1K pull-up resistance, when the current circuit is grounded, 3300ua current is generated, while for 100k pull-up resistance, 33ua is generated. Of course, for external power frequency interference, under the same conditions, 10K pull-up resistance has higher anti-interference degree;
When the partial voltage resistance is used for battery power detection, a resistance value of about 1m can be used. Due to the different impedance matching of single-chip microcomputer ADC (for ADC impedance matching, please refer to the problem of ADC impedance matching of single-chip microcomputer reading external voltage), it is recommended to add a primary voltage follower in the middle of signal acquisition. The follower needs low power consumption or separate power supply to avoid unnecessary power loss;
For scenes with light display, such as LED indication, reduce the LED brightness as much as possible.
